The present invention relates to a new and improved construction of transportation installation, and, more specifically, relates to apparatus for selecting a storey call at elevator systems or the like.
In its more particular aspects the invention relates to apparatus for selecting a storey call at elevator systems, which comprises storage elements controllable by means of storey call transmitters and storing the storey calls. The system further contains a scanner device which continuously scans in succession the storage elements from the lowermost to the uppermost and from the uppermost to the lowermost storey, the scanner device producing a signal sequence corresponding to the stored storey calls. Further, there is provided one selector which signals the location of at least one elevator cabin, and upon coincidence of the scanner position and the elevator cabin-position signal there is produced a coincidence signal.
In the case of collective controls for elevators it is known to accomplish the existing calls not in accordance with their input as a function of time, rather in a sequence dependent upon the position and the direction of travel of the elevator cabin. On the other hand, in the case of individual travel controls there is strived for servicing of the infed calls from the standpoint of the time of input thereof.
A heretofore known collective control for one or a number of elevators grouped together into a group, which collective control is formed of contactless switching elements and designed in digital technology, has been disclosed in Swiss Pat. No. 387,903. Such control system comprises a time-dependent and a position-dependent stepping mechanism. The time-dependent stepping mechanism controlled by a generator producing a sequence of 400 signals per second samples the storage elements serving for storage of the storey calls in succession form the lowermost to the uppermost and from the uppermost to the lowermost storey in a continuous fashion and delivers a signal train corresponding to the stored storey calls. The position-dependent stepping mechanism, during travel of the elevator cabin from one storey, in each case produces a signal corresponding to the following storey in an UP-direction or DOWN-direction, respectively. Now if the scanning position and the position signal of the elevator cabin coincide, then there is produced a coincidence signal. When the coincidence signal appears in conjunction with a signal, corresponding to a stored storey call, of the signal sequence or train delivered by the time-dependent stepping mechanism, then there is produced a holding signal which is delivered to the travel control of the elevator. In this way there is always selected and serviced the storey call situated closest to the position of the elevator cabin, thereby avoiding unnecessary idle travel of the elevator cabin.
A drawback of such type collective control particularly resides in the fact that even storey calls which have arrived at a later point in time may be serviced prior to earlier infed storey calls, so that there can arise unconscionably long waiting times at certain of the storeys of the building or structure.
A known apparatus for placing in order the servicing sequence of storey calls in not afflicted with this drawback. In this case there is provided a single travel control wherein there is extensively taken into account the sequence as a function of time of the input of the storey calls when they are serviced. This apparatus is provided for each storey with an additional storage element which is connected in circuit with a blocking and release device. A scanning device which scans the storage elements storing the storey calls controls the blocking and release device such that the storey calls are associated with timewise successive servicing stages. Thus, the storey calls which are infed during a servicing stage are blocked by means of the blocking device and only then serviced during the subsequent servicing stage after release by the blocking device.
The drawback of this apparatus resides in the fact that there can arise longer idle travel of the elevator cabin, since the storey calls are serviced independent of the position of the elevator cabin in accordance with the timewise sequence of input of the storey calls.